Project description:Muscle development and growth is an economically important process in the pig.The neonatal period is another important stage for the pig when the most rapid gain occurring in skeletal muscle.Gene expresseion changes during fetal and postnatal skeletal muscle development that can be used to enhance pig production efficiency, as well as for comparative developmental biology using the pig as a model for other mammalian species. We used microarrays to detail the global programme of gene expression level at different stages of postnatal development. Pig skeletal muscles were selected at different stages of post-natal development for RNA extraction and hybridization on Affymetrix microarrays.So,we sampled at four time-points: within 24 hours after birth (0d),7 days after birth (7d), 14 days after birth (14d), 21 days after birth (21d).
Project description:Muscle development and growth is an economically important process in the pig.The neonatal period is another important stage for the pig when the most rapid gain occurring in skeletal muscle.Gene expresseion changes during fetal and postnatal skeletal muscle development that can be used to enhance pig production efficiency, as well as for comparative developmental biology using the pig as a model for other mammalian species. We used microarrays to detail the global programme of gene expression level at different stages of postnatal development.
Project description:Comprehensive analyses of miRNAs expression were performed using miRNA microarrays during osteogenic differentiation of PDGFRa+ mesenchymal progenitors isolated from human skeletal muscle to identify miRNAs that are involved in osteogenesis of PDGFRa+ mesenchymal progenitors.
Project description:Bone marrow stromal cells (BMSCs) were isolated from the femora and tibiae of irtTA-GBD*-TAg transgenic mice. Using cellular cloning we established skeletal progenitors with unipotent osteogenic and adipogenic properties. Previous RNA-seq analysis of more progenitor types revealed differential expression in members of the Interferon-gamma (IFNγ) signaling pathway. Treatment of adipogenic progenitors with IFNγ inhibited adipogenesis and promoted osteogenesis. RNA-seq analysis of osteogenic, adipogenic and IFNγ treated adipogenic clones revealed factors controlling the osteogenic versus adipogenic commitment of bone marrow skeletal progenitors.
Project description:Androgens exert their effects primarily by binding to the androgen receptor (AR), a ligand-dependent nuclear receptor. While androgens have anabolic effects on skeletal muscle, previous studies reported that AR functions in myofibers to regulate skeletal muscle quality, rather than skeletal muscle mass. Therefore, the anabolic effects of androgens are exerted via extra-myofiber cells or tissues. In this context, the cellular and molecular mechanisms of AR in mesenchymal progenitors, which play a crucial role in maintaining skeletal muscle homeostasis, remain largely unknown. In this study, we demonstrated expression of AR in mesenchymal progenitors and found that targeted AR ablation in mesenchymal progenitors reduced limb muscle mass in mature adult, but not young or aged, male mice, although fatty infiltration of muscle was not affected. The absence of AR in mesenchymal progenitors led to remarkable perineal muscle hypotrophy, regardless of age, due to abnormal regulation of transcripts associated with apoptosis and proteolysis. Additionally, we revealed that AR in mesenchymal progenitors regulates the expression of insulin-like growth factor 1, which can increase skeletal muscle mass in a paracrine manner. These findings indicate that the anabolic effects of androgens indirectly regulate skeletal muscle mass via, at least in part, AR signaling in mesenchymal progenitors.
